Abstract

Background

As weight gain is one of the most frequently cited reasons for not using and for discontinuing
hormonal contraceptives, in an open-label, single-arm, multicentre clinical study
we evaluated the effect of the ethinylestradiol/norelgestromin contraceptive patch
(EVRA, Janssen-Cilag International, Belgium) on body composition using bioelectrical
impedance analysis (BIA).

Methods

Body weight and impedance vector components (resistance (R) and reactance (Xc), at
50 kHz frequency, Akern-RJL Systems analyzer) were recorded before entry, after 1,
3 and 6 months in 182 Italian healthy women aged 29 yr (18 to 45), and with BMI 21.8
kg/m2 (16 to 31). Total body water (TBW) was estimated with a BIA regression equation. Vector
BIA was performed with the RXc mean graph method and the Hotelling's T2 test for paired and unpaired data.

Conclusion

After 6 months of treatment with the ethinylestradiol/norelgestromin contraceptive
patch we found a minimal, clinically not relevant, increase in body weight less than
1 kg that could be attributed to an adaptive interstitial gel hydration. This fluctuation
is physiological as confirmed by the lack of any effect on blood pressure. This could
be useful in increasing women's choice, acceptability and compliance of the ethinylestradiol/norelgestromin
contraceptive patch.